反应详情

A solution of n-butyl lithium (100 mL, 1.6 M, 160 mmol) in hexanes was added over 2 min. to a stirred solution of 2-bromopyridine (15.0 mL, 24.9 g, 157 mmol) in 500 mL of ether cooled in a dry ice/isopropanol bath, causing a temporary rise in temperature to −47° C. After 25 min., the solution was transferred rapidly to a stirred 0° C. solution of diethyl oxalate (75 mL, 81 g, 550 mmol) in 1000 mL of ether. After 2 h at 0° C., the mixture was washed with saturated aq. sodium bicarbonate (900 mL), water (900 mL), and saturated aq. brine (450 mL). The organic layer was dried (magnesium sulfate), filtered, and evaporated. Distillation gave the title compound as 11.68 g of yellow liquid, B.p. 96-108° C. (0.3 mm Hg pressure). For the title compound:

1. temperaturecooled in a dry ice/isopropanol bath
2. customto −47° C
3. customwas transferred rapidly to a stirred 0° C.
4. waitAfter 2 h at 0° C.
5. washthe mixture was washed with saturated aq. sodium bicarbonate (900 mL), water (900 mL), and saturated aq. brine (450 mL)
6. dry with materialThe organic layer was dried (magnesium sulfate)
7. filtrationfiltered
8. customevaporated
9. distillationDistillation